The purpose of this proposal is to conduct an efficacy trial to determine whether Dialectical Behavior Therapy (DBT) added to suboxone (an opiate drug replacement) is an efficacious treatment for suicidal opiate addicts with Borderline Personality Disorder (BPD) characteristics and to analyze factors that influence efficacy in this population in order to improve the treatment. The combination of suicidality with substance abuse, particularly when other Axis I or II disorders are present, significantly compromises treatment outcome, and the purpose of this study is to investigate the efficacy of DBT added to suboxone as an effective treatment for this population. DBT, originally developed for chronically suicidal women with borderline personality disorder (BPD), is a synthesis of behavior therapy strategies aimed at change, and validation strategies aimed at acceptance, both held together by a set of dialectical strategies and underlying assumptions. DBT has been adapted for BPD substance abusers by the addition of 1) specific targets relevant to drug use, 2) a set of attachment strategies, 3) greater reliance on arbitrary reinforcers at treatment start, 4) weekly urinalysis, and 5) an opiate drug-replacement program (suboxone, i.e., buprenorphine in combination with naloxone) plus DBT clinical management. The research proposed here is a two arm, randomized clinical trial comparing a one year treatment program of DBT + suboxone for heroin addicted individuals to a one year program of Treatment-as-Usual (TAU) + suboxone. Treatment-as-usual will consist of the standard drug counseling and group therapies offered at area methadone clinics plus suboxone. Participants in both conditions will be prescribed psychotropic medications as needed. One hundred and thirty-six individuals (68 per condition) with opiate dependence, high suicidality and meeting a minimum of four BPD criterion will be enrolled in a one-year treatment and a one-year follow-up assessment. Assessments measuring drug use, suicidal behaviors, retention and other treatment-related behaviors, general psychopathology, and increases in behavioral skills will be given at four month intervals for the entire two years. Results will be analyzed using HLM and other regression-based procedures.